Many processes involving fluids, which can be liquid or gases, require that the fluids be mixed. Examples include the fuel intake process in internal combustion engines, the mixing of chemicals in the chemical processing industry and the injection of fluorine into hydrogen for pulsed HF lasers.
The mixing of fluids has been commonly performed by injecting a steady jet of one fluid through a nozzle into a volume of another fluid. However, the maximum mixing rate of fluids obtainable with a steady jet is not always fast enough for some applications. A faster method for mixing gases was developed in which a series of short pulses of one gas were injected into a volume of another gas. Each pulse of injected gas lasts only milliseconds and produces small puffs or vortices of the injected gas within the volume of the other gas. The small puffs of gas increase the surface area between the two gases, thereby, increasing the rate of mixing.